This problem is still reproducible on current Gnash git version, @bwy's
test file (file #18005) is still showing a filled triangle. @strk's patch
(file #18379) doesn't seem to apply on current codebase anymore.

I have made another test SWF file (using libming's makeswf) which tries to
re-demonstate this problem on both object filling and stroking, and also
include point-based `MovieClip.hitTest()` checks on the resulting shape.

You'd see that the code rendered as a filled pentagon with star-shaped hole
instead, and two lines drawn are also closed in loop. Point-based
`MovieClip.hitTest()` checks on the shape are also mostly failing.

The attached fills.as contain more tests which fail with current gnash, and for which I already implemented fixes.
Note that the yellow stroked square behaves in odd ways, leaving leaking fills with pp 9 and using smaller stroke thickness in pp 10.

The problem is that the call to lineStyle forces closeup of the current shape. I've tried having last lineStyle call use a different color to see if that should make a difference, but NOPE: the adobe player still considers it a single rectangle. No forced closeup.